js实现div模拟模态对话框展现URL内容

<script>
function sAlert(str){
 var msgw,msgh,bordercolor;
 msgw=800;//提示窗口的宽度
 msgh=600;//提示窗口的高度
 titleheight=25 //提示窗口标题高度
 bordercolor="#336699";//提示窗口的边框颜色
 titlecolor="#99CCFF";//提示窗口的标题颜色
 var sWidth,sHeight;
 sWidth=document.body.offsetWidth;
 sHeight=screen.height;
 var bgObj=document.createElement("div");
 bgObj.setAttribute('id','bgDiv');
 bgObj.style.position="absolute";
 bgObj.style.top="0";
 bgObj.style.background="#777";
 bgObj.style.filter="progid:DXImageTransform.Microsoft.Alpha(style=3,opacity=25,finishOpacity=75";
 bgObj.style.opacity="0.6";
 bgObj.style.left="0";
 bgObj.style.width=sWidth + "px";
 bgObj.style.height=sHeight + "px";
 bgObj.style.zIndex = "10000";
 document.body.appendChild(bgObj);
 var msgObj=document.createElement("div")
 msgObj.setAttribute("id","msgDiv");
 msgObj.setAttribute("align","center");
 msgObj.style.background="white";
 msgObj.style.border="1px solid " + bordercolor;
  msgObj.style.position = "absolute";
 msgObj.style.left = "60%";
   msgObj.style.top = "20%";
   msgObj.style.font="12px/1.6em Verdana, Geneva, Arial, Helvetica, sans-serif";
   msgObj.style.marginLeft = "-525px" ;
   msgObj.style.marginTop = -75+document.documentElement.scrollTop+"px";
   msgObj.style.width = msgw + "px";
   msgObj.style.height =msgh + "px";
   msgObj.style.textAlign = "center";
   msgObj.style.lineHeight ="25px";
   msgObj.style.zIndex = "10001";
  var title=document.createElement("h4");
  title.setAttribute("id","msgTitle");
  title.setAttribute("align","right");
  title.style.margin="0";
  title.style.padding="3px";
  title.style.background=bordercolor;
  title.style.filter="progid:DXImageTransform.Microsoft.Alpha(startX=20, startY=20, finishX=100, finishY=100,style=1,opacity=75,finishOpacity=100);";
  title.style.opacity="0.75";
  title.style.border="1px solid " + bordercolor;
  title.style.height="18px";
  title.style.font="12px Verdana, Geneva, Arial, Helvetica, sans-serif";
  title.style.color="white";
  title.style.cursor="pointer";
  title.innerHTML="关闭";
  title.onclick=function(){
  document.body.removeChild(bgObj);
   document.getElementById("msgDiv").removeChild(title);
   document.body.removeChild(msgObj);
   }
  document.body.appendChild(msgObj);
  document.getElementById("msgDiv").appendChild(title);
  var txt=document.createElement("p");
  txt.style.margin="1em 0"
  txt.setAttribute("id","msgTxt");
  txt.innerHTML=str;
  document.getElementById("msgDiv").appendChild(txt);
  }
function ajax_form(url)
{
 $.post(url,
 {Action:"POST"},
 function (data)
 {
  sAlert(data);
 }, 
 "html");
}
</script>